I am trying to use this library in a large application, and when I link it I get the errors pasted below. I have removed all places where the HardwareSerial.h library exists, and removed all Serial1 and Serial calls. I can build the samples. I realize the cause is because the compiler must be finding the original Serial library somewhere, but how to find it? Any hints?

Interesting, I see it's not working out of the box with maniacbug-mighty-1284p

__vector_20 is USART0_RX_vect. The 1284P defines the USART0 vectors, HardwareSerial picks them up. Shouldn't this also have the same problem on a Mega?

Looks like this library is demanding access to the USART0_RX_vect?

Oh? I was able to build a few of the examples that came with this library using your cores. I had suspected it was a core issue, but after I was able to build the examples I assumed it must be my code.

If I remove the HardwareSerial.cpp file, then the compilation fails. Its getting dragged in somewhere.

Okay, when I use that beta I can link if I remove another library from my system. I was taking a look to see how I might be able to modify that library, and I looked into your headers and saw that in sdFatUtil.h:

Thanks Lain, but nowhere in my code am I using Serial or Serial1 any longer. I found the library that I need to exclude to "fix" the problem, but I can't see anywhere in that library where Serial or Serial1 is being used either. I sent a note to the author of the other library, perhaps he will have an idea.

Ah! I take it back, thanks sixeyes! That other library had a diagnostic function that was in fact using Serial. I commented it out, and all is good now, thanks! With any luck, the new SD Beta Library will work well and I'll be off to the races!